10 resultados para Intention of voluntary departure
em AMS Tesi di Dottorato - Alm@DL - Università di Bologna
Resumo:
The treatment of the Cerebral Palsy (CP) is considered as the “core problem” for the whole field of the pediatric rehabilitation. The reason why this pathology has such a primary role, can be ascribed to two main aspects. First of all CP is the form of disability most frequent in childhood (one new case per 500 birth alive, (1)), secondarily the functional recovery of the “spastic” child is, historically, the clinical field in which the majority of the therapeutic methods and techniques (physiotherapy, orthotic, pharmacologic, orthopedic-surgical, neurosurgical) were first applied and tested. The currently accepted definition of CP – Group of disorders of the development of movement and posture causing activity limitation (2) – is the result of a recent update by the World Health Organization to the language of the International Classification of Functioning Disability and Health, from the original proposal of Ingram – A persistent but not unchangeable disorder of posture and movement – dated 1955 (3). This definition considers CP as a permanent ailment, i.e. a “fixed” condition, that however can be modified both functionally and structurally by means of child spontaneous evolution and treatments carried out during childhood. The lesion that causes the palsy, happens in a structurally immature brain in the pre-, peri- or post-birth period (but only during the firsts months of life). The most frequent causes of CP are: prematurity, insufficient cerebral perfusion, arterial haemorrhage, venous infarction, hypoxia caused by various origin (for example from the ingestion of amniotic liquid), malnutrition, infection and maternal or fetal poisoning. In addition to these causes, traumas and malformations have to be included. The lesion, whether focused or spread over the nervous system, impairs the whole functioning of the Central Nervous System (CNS). As a consequence, they affect the construction of the adaptive functions (4), first of all posture control, locomotion and manipulation. The palsy itself does not vary over time, however it assumes an unavoidable “evolutionary” feature when during growth the child is requested to meet new and different needs through the construction of new and different functions. It is essential to consider that clinically CP is not only a direct expression of structural impairment, that is of etiology, pathogenesis and lesion timing, but it is mainly the manifestation of the path followed by the CNS to “re”-construct the adaptive functions “despite” the presence of the damage. “Palsy” is “the form of the function that is implemented by an individual whose CNS has been damaged in order to satisfy the demands coming from the environment” (4). Therefore it is only possible to establish general relations between lesion site, nature and size, and palsy and recovery processes. It is quite common to observe that children with very similar neuroimaging can have very different clinical manifestations of CP and, on the other hand, children with very similar motor behaviors can have completely different lesion histories. A very clear example of this is represented by hemiplegic forms, which show bilateral hemispheric lesions in a high percentage of cases. The first section of this thesis is aimed at guiding the interpretation of CP. First of all the issue of the detection of the palsy is treated from historical viewpoint. Consequently, an extended analysis of the current definition of CP, as internationally accepted, is provided. The definition is then outlined in terms of a space dimension and then of a time dimension, hence it is highlighted where this definition is unacceptably lacking. The last part of the first section further stresses the importance of shifting from the traditional concept of CP as a palsy of development (defect analysis) towards the notion of development of palsy, i.e., as the product of the relationship that the individual however tries to dynamically build with the surrounding environment (resource semeiotics) starting and growing from a different availability of resources, needs, dreams, rights and duties (4). In the scientific and clinic community no common classification system of CP has so far been universally accepted. Besides, no standard operative method or technique have been acknowledged to effectively assess the different disabilities and impairments exhibited by children with CP. CP is still “an artificial concept, comprising several causes and clinical syndromes that have been grouped together for a convenience of management” (5). The lack of standard and common protocols able to effectively diagnose the palsy, and as a consequence to establish specific treatments and prognosis, is mainly because of the difficulty to elevate this field to a level based on scientific evidence. A solution aimed at overcoming the current incomplete treatment of CP children is represented by the clinical systematic adoption of objective tools able to measure motor defects and movement impairments. A widespread application of reliable instruments and techniques able to objectively evaluate both the form of the palsy (diagnosis) and the efficacy of the treatments provided (prognosis), constitutes a valuable method able to validate care protocols, establish the efficacy of classification systems and assess the validity of definitions. Since the ‘80s, instruments specifically oriented to the analysis of the human movement have been advantageously designed and applied in the context of CP with the aim of measuring motor deficits and, especially, gait deviations. The gait analysis (GA) technique has been increasingly used over the years to assess, analyze, classify, and support the process of clinical decisions making, allowing for a complete investigation of gait with an increased temporal and spatial resolution. GA has provided a basis for improving the outcome of surgical and nonsurgical treatments and for introducing a new modus operandi in the identification of defects and functional adaptations to the musculoskeletal disorders. Historically, the first laboratories set up for gait analysis developed their own protocol (set of procedures for data collection and for data reduction) independently, according to performances of the technologies available at that time. In particular, the stereophotogrammetric systems mainly based on optoelectronic technology, soon became a gold-standard for motion analysis. They have been successfully applied especially for scientific purposes. Nowadays the optoelectronic systems have significantly improved their performances in term of spatial and temporal resolution, however many laboratories continue to use the protocols designed on the technology available in the ‘70s and now out-of-date. Furthermore, these protocols are not coherent both for the biomechanical models and for the adopted collection procedures. In spite of these differences, GA data are shared, exchanged and interpreted irrespectively to the adopted protocol without a full awareness to what extent these protocols are compatible and comparable with each other. Following the extraordinary advances in computer science and electronics, new systems for GA no longer based on optoelectronic technology, are now becoming available. They are the Inertial and Magnetic Measurement Systems (IMMSs), based on miniature MEMS (Microelectromechanical systems) inertial sensor technology. These systems are cost effective, wearable and fully portable motion analysis systems, these features gives IMMSs the potential to be used both outside specialized laboratories and to consecutive collect series of tens of gait cycles. The recognition and selection of the most representative gait cycle is then easier and more reliable especially in CP children, considering their relevant gait cycle variability. The second section of this thesis is focused on GA. In particular, it is firstly aimed at examining the differences among five most representative GA protocols in order to assess the state of the art with respect to the inter-protocol variability. The design of a new protocol is then proposed and presented with the aim of achieving gait analysis on CP children by means of IMMS. The protocol, named ‘Outwalk’, contains original and innovative solutions oriented at obtaining joint kinematic with calibration procedures extremely comfortable for the patients. The results of a first in-vivo validation of Outwalk on healthy subjects are then provided. In particular, this study was carried out by comparing Outwalk used in combination with an IMMS with respect to a reference protocol and an optoelectronic system. In order to set a more accurate and precise comparison of the systems and the protocols, ad hoc methods were designed and an original formulation of the statistical parameter coefficient of multiple correlation was developed and effectively applied. On the basis of the experimental design proposed for the validation on healthy subjects, a first assessment of Outwalk, together with an IMMS, was also carried out on CP children. The third section of this thesis is dedicated to the treatment of walking in CP children. Commonly prescribed treatments in addressing gait abnormalities in CP children include physical therapy, surgery (orthopedic and rhizotomy), and orthoses. The orthotic approach is conservative, being reversible, and widespread in many therapeutic regimes. Orthoses are used to improve the gait of children with CP, by preventing deformities, controlling joint position, and offering an effective lever for the ankle joint. Orthoses are prescribed for the additional aims of increasing walking speed, improving stability, preventing stumbling, and decreasing muscular fatigue. The ankle-foot orthosis (AFO), with a rigid ankle, are primarily designed to prevent equinus and other foot deformities with a positive effect also on more proximal joints. However, AFOs prevent the natural excursion of the tibio-tarsic joint during the second rocker, hence hampering the natural leaning progression of the whole body under the effect of the inertia (6). A new modular (submalleolar) astragalus-calcanear orthosis, named OMAC, has recently been proposed with the intention of substituting the prescription of AFOs in those CP children exhibiting a flat and valgus-pronated foot. The aim of this section is thus to present the mechanical and technical features of the OMAC by means of an accurate description of the device. In particular, the integral document of the deposited Italian patent, is provided. A preliminary validation of OMAC with respect to AFO is also reported as resulted from an experimental campaign on diplegic CP children, during a three month period, aimed at quantitatively assessing the benefit provided by the two orthoses on walking and at qualitatively evaluating the changes in the quality of life and motor abilities. As already stated, CP is universally considered as a persistent but not unchangeable disorder of posture and movement. Conversely to this definition, some clinicians (4) have recently pointed out that movement disorders may be primarily caused by the presence of perceptive disorders, where perception is not merely the acquisition of sensory information, but an active process aimed at guiding the execution of movements through the integration of sensory information properly representing the state of one’s body and of the environment. Children with perceptive impairments show an overall fear of moving and the onset of strongly unnatural walking schemes directly caused by the presence of perceptive system disorders. The fourth section of the thesis thus deals with accurately defining the perceptive impairment exhibited by diplegic CP children. A detailed description of the clinical signs revealing the presence of the perceptive impairment, and a classification scheme of the clinical aspects of perceptual disorders is provided. In the end, a functional reaching test is proposed as an instrumental test able to disclosure the perceptive impairment. References 1. Prevalence and characteristics of children with cerebral palsy in Europe. Dev Med Child Neurol. 2002 Set;44(9):633-640. 2. Bax M, Goldstein M, Rosenbaum P, Leviton A, Paneth N, Dan B, et al. Proposed definition and classification of cerebral palsy, April 2005. Dev Med Child Neurol. 2005 Ago;47(8):571-576. 3. Ingram TT. A study of cerebral palsy in the childhood population of Edinburgh. Arch. Dis. Child. 1955 Apr;30(150):85-98. 4. Ferrari A, Cioni G. The spastic forms of cerebral palsy : a guide to the assessment of adaptive functions. Milan: Springer; 2009. 5. Olney SJ, Wright MJ. Cerebral Palsy. Campbell S et al. Physical Therapy for Children. 2nd Ed. Philadelphia: Saunders. 2000;:533-570. 6. Desloovere K, Molenaers G, Van Gestel L, Huenaerts C, Van Campenhout A, Callewaert B, et al. How can push-off be preserved during use of an ankle foot orthosis in children with hemiplegia? A prospective controlled study. Gait Posture. 2006 Ott;24(2):142-151.
Resumo:
This research aims to identify the guidelines that are opposed to Judaism in the body of the work Dialogue with Trypho of Justin Martyr, using the methodology engendered by Norbert Elias and John L. Scotson in their work, The Established and the Outsiders. As a result, our research intends to contribute to unveil another aspect of Justin’s work, considered by many scholars as a proselytistic tool; by taking it as a document builder of the Christian identity trough its dissociation from Judaism. For this reason, this thesis investigates and reviews the socio-cultural and political environment that gave rise to Roman Christianity, taking into consideration Christian internal conflicts and the resulting dichotomies within the Roman Christian community, as a result of its departure from its Jewish matrix.
Resumo:
Although its great potential as low to medium temperature waste heat recovery (WHR) solution, the ORC technology presents open challenges that still prevent its diffusion in the market, which are different depending on the application and the size at stake. Focusing on the micro range power size and low temperature heat sources, the ORC technology is still not mature due to the lack of appropriate machines and working fluids. Considering instead the medium to large size, the technology is already available but the investment is still risky. The intention of this thesis is to address some of the topical themes in the ORC field, paying special attention in the development of reliable models based on realistic data and accounting for the off-design performance of the ORC system and of each of its components. Concerning the “Micro-generation” application, this work: i) explores the modelling methodology, the performance and the optimal parameters of reciprocating piston expanders; ii) investigates the performance of such expander and of the whole micro-ORC system when using Hydrofluorocarbons as working fluid or their new low GWP alternatives and mixtures; iii) analyzes the innovative ORC reversible architecture (conceived for the energy storage), its optimal regulation strategy and its potential when inserted in typical small industrial frameworks. Regarding the “Industrial WHR” sector, this thesis examines the WHR opportunity of ORCs, with a focus on the natural gas compressor stations application. This work provides information about all the possible parameters that can influence the optimal sizing, the performance and thus the feasibility of installing an ORC system. New WHR configurations are explored: i) a first one, relying on the replacement of a compressor prime mover with an ORC; ii) a second one, which consists in the use of a supercritical CO2 cycle as heat recovery system.
Resumo:
Questa tesi riguarda l'analisi delle trasmissioni ad ingranaggi e delle ruote dentate in generale, nell'ottica della minimizzazione delle perdite di energia. È stato messo a punto un modello per il calcolo della energia e del calore dissipati in un riduttore, sia ad assi paralleli sia epicicloidale. Tale modello consente di stimare la temperatura di equilibrio dell'olio al variare delle condizioni di funzionamento. Il calcolo termico è ancora poco diffuso nel progetto di riduttori, ma si è visto essere importante soprattutto per riduttori compatti, come i riduttori epicicloidali, per i quali la massima potenza trasmissibile è solitamente determinata proprio da considerazioni termiche. Il modello è stato implementato in un sistema di calcolo automatizzato, che può essere adattato a varie tipologie di riduttore. Tale sistema di calcolo consente, inoltre, di stimare l'energia dissipata in varie condizioni di lubrificazione ed è stato utilizzato per valutare le differenze tra lubrificazione tradizionale in bagno d'olio e lubrificazione a “carter secco” o a “carter umido”. Il modello è stato applicato al caso particolare di un riduttore ad ingranaggi a due stadi: il primo ad assi paralleli ed il secondo epicicloidale. Nell'ambito di un contratto di ricerca tra il DIEM e la Brevini S.p.A. di Reggio Emilia, sono state condotte prove sperimentali su un prototipo di tale riduttore, prove che hanno consentito di tarare il modello proposto [1]. Un ulteriore campo di indagine è stato lo studio dell’energia dissipata per ingranamento tra due ruote dentate utilizzando modelli che prevedano il calcolo di un coefficiente d'attrito variabile lungo il segmento di contatto. I modelli più comuni, al contrario, si basano su un coefficiente di attrito medio, mentre si può constatare che esso varia sensibilmente durante l’ingranamento. In particolare, non trovando in letteratura come varia il rendimento nel caso di ruote corrette, ci si è concentrati sul valore dell'energia dissipata negli ingranaggi al variare dello spostamento del profilo. Questo studio è riportato in [2]. È stata condotta una ricerca sul funzionamento di attuatori lineari vite-madrevite. Si sono studiati i meccanismi che determinano le condizioni di usura dell'accoppiamento vite-madrevite in attuatori lineari, con particolare riferimento agli aspetti termici del fenomeno. Si è visto, infatti, che la temperatura di contatto tra vite e chiocciola è il parametro più critico nel funzionamento di questi attuatori. Mediante una prova sperimentale, è stata trovata una legge che, data pressione, velocità e fattore di servizio, stima la temperatura di esercizio. Di tale legge sperimentale è stata data un'interpretazione sulla base dei modelli teorici noti. Questo studio è stato condotto nell'ambito di un contratto di ricerca tra il DIEM e la Ognibene Meccanica S.r.l. di Bologna ed è pubblicato in [3].
Resumo:
The thesis aims at inquiring into the issue of innovation and organizational and institutional change in the public administration with regard to the increasingly massive adoption of participatory devices and practices in various arenas of public policies. The field of reference regards transformations of the types of public actions and regulation systems, concerning governance. Together with the crisis of the public function and of the role played by the insitutions what is emerging are different levels of governement, both towards an over national and a local direction, and a plurality of social interlocutors, followed by a post-bureaucratic pattern of the public administration that is opening itself in the direction of environment and citizens. The public adminstration is no longer considered an inert object within the bureaucratic paradigm but as a series of communicative processes, choices, cultures and practices that actively builds itself and the environment it interacts with. Therefore, the output of the public administration isn’t the simple service being supplied but the relationship enacted with the citizen, relationship that becomes the constituent basis of adminstrative processes. The intention of thesis is to take into consideration the relation between innovation of the public administration and participatory experimentations and implementations regarded as exchanges in which citizens and the public administration hold talks and debates. The issue of the organizational change of the public administration as output and effect of inclusive deliberative practices has been analysed starting from an institutionalist approach, in other words examining the constituent features of institutions, “rediscovering” them with regard to their public nature, their ability to elaborate collective values and meanings, the social definition of problems and solutions. The participatory device employed by the Forlì city council that involved enterprises and cultural associations of the area in order to build a participatory Table, has been studied through a qualitative methodology (participant observation and semi-strutctured interviews). The analysis inquired into the public nature both of the participatory device and the administrative action itself as well as into elements pertaining the deliberative setting, the regulative reference framework and the actors which took part in the process.
Resumo:
Until recently the debate on the ontology of spacetime had only a philosophical significance, since, from a physical point of view, General Relativity has been made "immune" to the consequences of the "Hole Argument" simply by reducing the subject to the assertion that solutions of Einstein equations which are mathematically different and related by an active diffeomorfism are physically equivalent. From a technical point of view, the natural reading of the consequences of the "Hole Argument” has always been to go further and say that the mathematical representation of spacetime in General Relativity inevitably contains a “superfluous structure” brought to light by the gauge freedom of the theory. This position of apparent split between the philosophical outcome and the physical one has been corrected thanks to a meticulous and complicated formal analysis of the theory in a fundamental and recent (2006) work by Luca Lusanna and Massimo Pauri entitled “Explaining Leibniz equivalence as difference of non-inertial appearances: dis-solution of the Hole Argument and physical individuation of point-events”. The main result of this article is that of having shown how, from a physical point of view, point-events of Einstein empty spacetime, in a particular class of models considered by them, are literally identifiable with the autonomous degrees of freedom of the gravitational field (the Dirac observables, DO). In the light of philosophical considerations based on realism assumptions of the theories and entities, the two authors then conclude by saying that spacetime point-events have a degree of "weak objectivity", since they, depending on a NIF (non-inertial frame), unlike the points of the homogeneous newtonian space, are plunged in a rich and complex non-local holistic structure provided by the “ontic part” of the metric field. Therefore according to the complex structure of spacetime that General Relativity highlights and within the declared limits of a methodology based on a Galilean scientific representation, we can certainly assert that spacetime has got "elements of reality", but the inevitably relational elements that are in the physical detection of point-events in the vacuum of matter (highlighted by the “ontic part” of the metric field, the DO) are closely dependent on the choice of the global spatiotemporal laboratory where the dynamics is expressed (NIF). According to the two authors, a peculiar kind of structuralism takes shape: the point structuralism, with common features both of the absolutist and substantival tradition and of the relationalist one. The intention of this thesis is that of proposing a method of approaching the problem that is, at least at the beginning, independent from the previous ones, that is to propose an approach based on the possibility of describing the gravitational field at three distinct levels. In other words, keeping the results achieved by the work of Lusanna and Pauri in mind and following their underlying philosophical assumptions, we intend to partially converge to their structuralist approach, but starting from what we believe is the "foundational peculiarity" of General Relativity, which is that characteristic inherent in the elements that constitute its formal structure: its essentially geometric nature as a theory considered regardless of the empirical necessity of the measure theory. Observing the theory of General Relativity from this perspective, we can find a "triple modality" for describing the gravitational field that is essentially based on a geometric interpretation of the spacetime structure. The gravitational field is now "visible" no longer in terms of its autonomous degrees of freedom (the DO), which, in fact, do not have a tensorial and, therefore, nor geometric nature, but it is analyzable through three levels: a first one, called the potential level (which the theory identifies with the components of the metric tensor), a second one, known as the connections level (which in the theory determine the forces acting on the mass and, as such, offer a level of description related to the one that the newtonian gravitation provides in terms of components of the gravitational field) and, finally, a third level, that of the Riemann tensor, which is peculiar to General Relativity only. Focusing from the beginning on what is called the "third level" seems to present immediately a first advantage: to lead directly to a description of spacetime properties in terms of gauge-invariant quantites, which allows to "short circuit" the long path that, in the treatises analyzed, leads to identify the "ontic part” of the metric field. It is then shown how to this last level it is possible to establish a “primitive level of objectivity” of spacetime in terms of the effects that matter exercises in extended domains of spacetime geometrical structure; these effects are described by invariants of the Riemann tensor, in particular of its irreducible part: the Weyl tensor. The convergence towards the affirmation by Lusanna and Pauri that the existence of a holistic, non-local and relational structure from which the properties quantitatively identified of point-events depend (in addition to their own intrinsic detection), even if it is obtained from different considerations, is realized, in our opinion, in the assignment of a crucial role to the degree of curvature of spacetime that is defined by the Weyl tensor even in the case of empty spacetimes (as in the analysis conducted by Lusanna and Pauri). In the end, matter, regarded as the physical counterpart of spacetime curvature, whose expression is the Weyl tensor, changes the value of this tensor even in spacetimes without matter. In this way, going back to the approach of Lusanna and Pauri, it affects the DOs evolution and, consequently, the physical identification of point-events (as our authors claim). In conclusion, we think that it is possible to see the holistic, relational, and non-local structure of spacetime also through the "behavior" of the Weyl tensor in terms of the Riemann tensor. This "behavior" that leads to geometrical effects of curvature is characterized from the beginning by the fact that it concerns extensive domains of the manifold (although it should be pointed out that the values of the Weyl tensor change from point to point) by virtue of the fact that the action of matter elsewhere indefinitely acts. Finally, we think that the characteristic relationality of spacetime structure should be identified in this "primitive level of organization" of spacetime.
Resumo:
Il concetto di contaminazione fra architettura ed arti plastiche e figurative è molto antico. La dicotomia arte-architettura, sancita in via definitiva con il moderno museo di spoliazione napoleonica, non può che essere considerata una variazione neo-tecnicista sulla quale, non sempre giustamente, sono andati assestandosi gli insegnamenti delle scuole politecniche. Non così è sempre stato. Come il tempio greco può essere considerato un’opera plastica nel suo complesso, esempio tra i primi di fusione tra arte e architettura, moltissimi sono gli esempi che hanno guidato la direzione della ricerca che si è intesa perseguire. Molti sono gli esempi del passato che ci presentano figure di architetto-artista: un esempio fra tutti Michelangelo Buonarroti; come per altro non è nuovo, per l’artista puro, cimentarsi nella progettazione dello spazio architettonico o urbano, o per l'architetto essere coinvolto dalle indagini della ricerca artistica a lui contemporanea dalla quale trarre suggestioni culturali. Le rappresentazioni dei linguaggi visivi sono il frutto di contaminazioni che avvengono su diversi livelli e in più direzioni. Spesso le ricerche artistiche più significative hanno anticipato o influenzato il mondo del design, dell’architettura, della comunicazione. L’intenzione della ricerca è stata quindi approfondire, attraverso un viaggio nel Novecento, con particolare attenzione al Secondo Dopoguerra, i fenomeni culturali che hanno prodotto i più significativi sviluppi stilistici nell’ambito della ricerca e del rinnovo del linguaggio architettonico. Il compito, parafrasando Leonardo Benevolo, non è stato quello di elencare le singole battute della discussione ma di riconoscere gli interventi fruttuosi a lunga scadenza. Mutuando gli insegnamenti della scuola del Bauhaus, arte e architettura sono state affiancate perché considerate espressioni strettamente relazionate di coevi fenomeni culturali. L’obiettivo ha puntato all’individuazione dei meccanismi delle interazioni tra discipline, cercando di delineare il profilo della complessità dell’espressione del contemporaneo in architettura.
Resumo:
La libertad de establecimiento y la movilidad de las empresas juegan un papel fundamental en el proceso comunitario de integración. Las empresas buscan nuevas formas de cooperación e integración que les permitan ocupar cuotas de mercado cada vez más importantes. De entre las modalidades de integración y cooperación que tienen a su disposición, la fusión transfronteriza de sociedades es, sin duda, una de las más relevantes. Es evidente que las fusiones de sociedades pertenecientes a Estados miembros distintos podrían tener una enorme importancia en el proceso de integración del mercado único. Sin embargo, la posibilidad de llevar a cabo con éxito una fusión transfronteriza en el ámbito comunitario era improbable hasta época reciente. Dos tipos de impedimentos la dificultaban: por una parte, obstáculos a la libertad de establecimiento por parte de los ordenamientos jurídicos de los Estados miembros; por otro, obstáculos de Derecho internacional privado. En cambio, hoy la mayor parte de estos impedimentos han sido superados gracias, en primer lugar, al progresivo reconocimiento del derecho de establecimiento de las sociedades por el Tribunal de Justicia, y en segundo, a la importante Directiva 2005/56/CE relativa a las fusiones transfronterizas de sociedades de capital. Esta Directiva impone a los Estados miembros una serie de normas de mínimos de derecho material a fin de armonizar la tutela de los intereses de los sujetos implicados más débiles (sobre todo, los trabajadores y los socios). De igual manera, establece una serie de normas de conflicto para resolver la cuestión de la ley aplicable a las fusiones transfronterizas. Este trabajo tiene como objetivo principal valorar la relevancia de los pronunciamientos del Tribunal de Justicia y de las actuaciones del legislador europeo orientados a impedir las restricciones a las fusiones transfronterizas de sociedades en el territorio comunitario.
Resumo:
This thesis aimed at addressing some of the issues that, at the state of the art, avoid the P300-based brain computer interface (BCI) systems to move from research laboratories to end users’ home. An innovative asynchronous classifier has been defined and validated. It relies on the introduction of a set of thresholds in the classifier, and such thresholds have been assessed considering the distributions of score values relating to target, non-target stimuli and epochs of voluntary no-control. With the asynchronous classifier, a P300-based BCI system can adapt its speed to the current state of the user and can automatically suspend the control when the user diverts his attention from the stimulation interface. Since EEG signals are non-stationary and show inherent variability, in order to make long-term use of BCI possible, it is important to track changes in ongoing EEG activity and to adapt BCI model parameters accordingly. To this aim, the asynchronous classifier has been subsequently improved by introducing a self-calibration algorithm for the continuous and unsupervised recalibration of the subjective control parameters. Finally an index for the online monitoring of the EEG quality has been defined and validated in order to detect potential problems and system failures. This thesis ends with the description of a translational work involving end users (people with amyotrophic lateral sclerosis-ALS). Focusing on the concepts of the user centered design approach, the phases relating to the design, the development and the validation of an innovative assistive device have been described. The proposed assistive technology (AT) has been specifically designed to meet the needs of people with ALS during the different phases of the disease (i.e. the degree of motor abilities impairment). Indeed, the AT can be accessed with several input devices either conventional (mouse, touchscreen) or alterative (switches, headtracker) up to a P300-based BCI.
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Questa ricerca, suddivisa in due parti, si concentra sulle problematiche connesse alla normazione della vita e dei corpi delle donne al tempo delle biotecnologie. La Parte I è una genealogia filosofico-politica che ripercorre le tappe analitico-concettuali del dibattito intorno a biopolitica e tecnoscienza, a partire dai contributi teorici di poststrutturalismo e femminismo neomaterialista, e risponde alle domande: Cosa sono diventati i corpi nell’attuale società bio-info-modificata? Qual'è il ruolo delle scienze nelle metamorfosi che interessano soggettività e rapporti di potere? La Parte II è una cartografia dei modi in cui le biotecnologie, riguardanti i corpi delle donne, si sono sviluppate e diffuse. Essa indaga in modo transdisciplinare come in Italia, e più in generale in Europa, sono state normate le tecniche di interruzione volontaria di gravidanza e fecondazione in vitro. Ampio spazio è dedicato ai modi in cui gli attori della bioetica, istituzionale e non, i medici, laici e cattolici, e le case farmaceutiche hanno affrontato questi temi e quello della contraccezione ormonale maschile. Medicina riproduttiva e rigenerativa sono tematizzate sempre in relazione al quadro normativo, per mostrare in che modo esso influenzi l’accesso ai diritti alla salute e all’autodeterminazione delle donne. Il quadro normativo è analizzato, a sua volta, alla luce dei fatti storici più rilevanti e delle culture più diffuse. L’obiettivo della ricerca è duplice: da un lato essa ha il fine di mostrare il modo in cui i corpi delle donne, e la relativa potenza generatrice, siano diventati uno snodo fondamentale nell’articolazione del biocontrollo e nell'apertura dei nuovi mercati legati a medicina riproduttiva e rigenerativa; dall’altro si propone di argomentare come un biodiritto flessibile, a contenuto storico variabile, condiviso e partecipato, sia un’ipotesi praticabile e virtuosa, utile all'eliminazione del gender gap ancora esistente in materia di diritti riproduttivi e sessuali.